The present invention is directed to the regeneration of water treatment media and, more particularly, to a water treatment unit having one or more media with a valve for the selective regeneration of the media, and to a method of regenerating the media.
Fluid treatment systems employing one or more fluid treatment media have been employed in the past for the treatment of various fluids, such as water, to remove various impurities and contaminants therefrom. In some of these systems, various different treatment media have been employed in serial relationship to each other so that for example one medium may have a beneficial effect on subsequent downstream media. For example, in HESKETT U.S. Pat. No. 5,415,770 it is disclosed that the use of certain finely divided metals, such as alloys of copper and zinc, may be employed as an upstream treatment medium to remove certain chemical constituents, such as residual chlorine, prior to subjecting water to other downstream water treatment media, such as activated carbon and/or an ion exchange medium. Removal of the chlorine is not only beneficial to the quality of the ultimate product, but it also improves the function, and life of the latter two media when present may be improved and extended.
In prior systems the several respective media are frequently located in several distinct units which are physically separated from each other and the fluids are passed through these distinct units in a serial fashion. These individual units can be individually serviced, but they are demanding of space and material. Where the several respective media are contained in a single container or tank, they are difficult to maintain separate from each other, particularly due to the wide disparity in weights and/or sizes of the respective media particles. Even where they can be maintained separate from each other, the placement of each of the media in the same tank makes it physically difficult to service or replace one medium without replacing the others due to their positioning relative to each other. Another disadvantage, particularly in small counter top water or tap mounted treatment units, such as shower head mounted units, is that no provision is usually possible to permit rinsing or backwashing of the media which, if possible, might greatly extend the life of the system and their respective media.
Another disadvantage in many water treatment units is that the flow through the treatment media during service is generally in a direction which tends to compact the medium. Thus, any dirt or other contaminants which are removed by the medium become trapped in the medium and accumulate to eventually clog the medium or interfere with its treatment function. When this occurs, it ends the life of the medium and requires its replacement.
It is the purpose of the present invention to avoid or eliminate the aforementioned disadvantages. In the present invention, a multimedia fluid treatment unit with an efficient control valve which is a part of the unit is provided which is compact, permits ready servicing of the unit and the utilization of a number of different media in the unit. In the present invention, the life of the unit is significantly extended and the effective amount of medium is reduced by selective arrangement of the several media relative to each other to remove compounds which might be harmful to some of the media, by providing for periodic rinsing and/or backwashing of the treatment medium, and/or by automatic regeneration of the medium upon initiation of normal fluid flow. Moreover, the portion of the unit which contains the media need only be simply manually rotated to effect such rinsing and backwashing. When needed, in the fluid treatment unit of the present invention any replacement and service of the unit and any treatment media therein are facilitated.
In one principal aspect of the present invention, a unit includes a rotatable valve which comprises a substantially disc shaped valve plate, a face on one side of the disc shaped valve plate, and a plurality of passages extending into the plate from openings in the face, with at least some of the passages extending through the thickness of the valve plate to communicate with the side of the plate opposite the face. The disc shaped valve plate is rotatable about an axis which extends at a substantial angle to the face. A valve housing having a face adjacent the valve plate face also has a plurality of passages therein which open to the valve housing face. A first of the valve housing passages communicates with a supply of fluid, a second of the valve housing passages communicates with a discharge for the fluid from the valve housing, and a third of the passages communicates with a drain from the valve housing. The valve plate is rotatable about its axis between a first position in which the fluid is supplied from the first passage in the valve housing to one of the passages through the valve plate, and from another of the passages through the valve plate to the second passage in the valve housing communicating with the discharge from the valve housing, and a second position in which the fluid is supplied from another of the passages in the valve housing to another of the passages through the valve plate, and from another of the passages through the valve plate to the third passage in the valve housing communicating with the drain from the valve housing.
In another principal aspect of the present invention, the faces are substantially planar and parallel to each other, and the axis of the plate is substantially perpendicular to the planar faces.
In still another principal aspect of the present invention, a plurality of seals on at least one of the faces are selectively alignable with ones of the passages which open through the other of the faces when the other of the faces is rotated relative to at least one of the faces as the valve plate is rotated.
In still another principal aspect of the present invention, the seals may comprise O-rings and/or spring loaded gaskets.
In still another principal aspect of the present invention, the unit also includes in combination with the rotatable valve, a housing containing at least one fluid treatment medium. When the valve plate is in the first position, the fluid is supplied from the first passage from the fluid supply in the valve housing to one of the passages through the valve plate and to the fluid treatment medium, and from the fluid treatment medium to another of the passages through the valve plate to the second passage in the valve housing communicating with the discharge from the valve housing to provide fluid which has been treated by the fluid treatment medium through the discharge. When the valve plate is in the second position, the fluid is supplied from another of the passages in the valve housing to another of the passages through the valve plate and to the fluid treatment medium, and from the fluid treatment medium to another of the passages through the valve plate and the third passage in the valve housing communicating with the drain from the valve housing to backwash the fluid treatment medium.
In still another principal aspect of the present invention, the valve plate is also rotatable to at least one or more additional positions which include a rinse position in which fluid passes from the fluid supply through the fluid treatment medium to rinse it and therefrom to the drain, an off position in which fluid flow through the unit is turned off or a bypass position in which fluid is bypassed around the fluid treatment medium from the fluid supply through the valve plate and to a fluid discharge from the valve housing.
In still. another principal aspect of the present invention, when the valve plate is in the second position, fluid is supplied from the fluid supply to the fluid treatment medium to backwash the fluid treatment medium.
In still another principal aspect of the present invention, the valve housing includes a passage for communication with a source of brine for regeneration of the fluid treatment medium, and when the valve plate is in the second position, fluid is supplied from the source of brine through the last mentioned passage to the fluid treatment medium to regenerate the fluid treatment medium.
In still another principal aspect of the present invention, the housing containing the fluid treatment medium is fixed to the valve plate, whereby the valve plate is rotated between the first and second positions by rotation of the housing.
In still another principal aspect of the present invention, a fluid treatment unit comprises a housing having a chamber therein which is of a given volume, and finely divided loose fluid treatment medium in the chamber and which occupies a volume which is substantially less than the given volume of the chamber when fluid to be treated is not flowing through the medium. The chamber has an inlet for introducing the fluid to be treated to the chamber and beneath the fluid treatment medium in the chamber, and an outlet to the chamber downstream of the fluid treatment medium for discharging the fluid which has been treated from the chamber. The unit is constructed and arranged to lift the loose fluid treatment medium in a controlled manner upon initiation of flow of fluid to be treated from the inlet to flush and remove contaminants from the medium, to suspend the medium during continuing flow of the fluid, and to permit the medium to settle to the bottom of the chamber when the flow of fluid has ceased.
In still another principal aspect of the present invention, the chamber has a height which is greater than its maximum width, and the chamber includes at least one portion intermediate its height which portion has a width substantially less than the maximum width to reduce the rate at which the medium is lifted in the chamber as the flow of fluid is initiated.
In still another principal aspect of the present invention, the cross-sectional area of the portion is about 5-50%, and more preferably about 10% of the cross-sectional area of the chamber at its maximum width.
In still another principal aspect of the present invention, a plurality of the portions are spaced from each other along the length of the chamber.
In still another principal aspect of the present invention, an additional inlet is positioned intermediate the length of the chamber and which is associated with the lesser width portion to introduce additional fluid to be treated to the chamber adjacent the lesser width portion.
In still another principal aspect of the present invention, the lesser width portion comprises a sleeve positioned in the chamber.
In still another principal aspect of the present invention, the medium is a particulate metal selected from the group consisting essentially of copper, zinc and mixtures thereof, and is preferably an alloy of copper and zinc.
In still another principal aspect of the present invention, a method of rapidly regenerating a finely divided loose fluid treatment medium upon initiation of the treatment of the fluid, comprises permitting the finely divided loose fluid treatment medium to settle into a bed following a preceding treatment of the fluid, by ceasing or reducing the fluid flow to an amount insufficient to suspend the medium, initiating the flow of fluid to be treated beneath the bed of the finely divided loose fluid treatment medium, with the flow as initiated being of sufficient magnitude to lift the finely divided loose fluid treatment medium from the bed while restraining the rate at which the medium is lifted to thoroughly separate and flush away contaminants that may have previously accumulated on the bed, and continuing to maintain the flow of fluid to be treated in a manner sufficient to continue to maintain the loose fluid treatment medium suspended in the flowing fluid during treatment of the fluid.
In still another principal aspect of the present invention, the method. includes selectively restraining the rate at which the medium is lifted at least at one to two locations over the path of the flow during the initiation of flow of fluid.
In still another principal aspect of the present invention, in the method the rate at which the medium is lifted is restrained by passing the lifted fluid treatment medium through a cross-sectional area which is about 5-50%, and more preferably about 10% of the maximum cross-sectional area of the bed.
In still another principal aspect of the present invention, the method includes introducing additional fluid to be treated at least at one location over the path of flow during the initiation of flow of fluid.
In still another principal aspect of the present invention, in the method of the invention, the medium is a particulate metal selected from the group consisting essentially of copper, zinc and mixtures thereof, and is preferably an alloy of copper and zinc.
In still another principal aspect of the present invention, the fluid being treated is water.
These and other objects, features and advantages of the present invention will be more clearly understood through a consideration of the following detailed description.